Support requested in this application is for the ongoing and expanding participation of the Division of Radiation Oncology of the University of California in San Francisco in the activities of the Radiation Therapy Oncology Group. Comprised of three hospitals, Moffitt, Mt. Zion and Franklin, the Division is staffed by eleven full-time faculty members, treating 2,000 new patients per year. The division has participated in the group since 1972, entering approximately 115 patients into the various Group Protocols, Pilot Studies, and Registry Protocols from Moffitt Hospital alone during the past year, even though support for our participation was not begun until September 30, 1977. The Principal Investigator is a member of the Head and Neck Committee, Combination Radiotherapy and Chemotherapy Subcommittee, Hematopoeitic Subcommittee, Californium-252 Subcommittee of the Radiation Therapy Oncology Group. The Associate Principal Investigator is the Chairman of the Radiobiology Committee and a member of the Publication Committee, Experimntal Design Committee, Lung Subcommittee, Metastasis (pulmonary) Subcommittee, Californium Subcommittee, Radiation Injury Subcommittee, Hyperthermia Subcommittee, and the Study Manager of Phase I Evaluation of Radiosensitizer Misonidazole, and all staff members serve on the working parties. The group has produced protocols for head and neck cancer, non-Hodgkin's lymphoma, brain metastasis, and hypoxic cell radiosensitizers, as well as providing input into other protocols. Support through this application will allow RTOG participation by the entire Division and increase the case accession rate to at least 150 new patients per year into the various RTOG protocols. Extensive continuing research into high LET radiotherapy, chemical and thermal modification of radiation effects is expected to lead to innovative protocols and correspondingly to increased accession of patients into studies sponsored by the RTOG.